Survey

[dblyle]

We have been asked to survey a 12 story hospital to develop plans for replacement of all horizontal DWV pipe in the building. What typical things would/should a plumbing engineer be looking for on a survey of this type?

Thanks...

 

[ChrisConley]

Location of horizontal DWV pipe would be the biggest thing... what else have you been asked to look for?

 

[dblyle]

We have done these types of surveys in the past and typically look for (as you mentioned) the location of the DWV pipe and the accuracy of the current as-built drawings. One of the projects we recently did has come back to bite us in that the plumbing contractor is having to spend an incredible amount of labor correcting slope problems in the building. Turns out the existing plumbing in the whole building is 100% sloped the wrong way. So, now instead of just replacing the pipe, he (the contractor) is haveing to re-route a considerable amount in order to get the correct slope on the pipe.

Given the conditions above the ceiling (with duct obstructions, conduit, etc), should the slope problems have been picked up on the original engineering survey? Keep in mind the original scope was just to replace the failing pipe.

 

[PEDARRIN2]

In the surveys I have done, the sanitary and the storm above the ceiling tended to be high up to avoid obstructions by other trade's. To be able to see if a pipe is sloped the wrong way when all you are doing is looking at its bottom can be difficult.

I would look for places where the pipe has or is failing. Look at ceiling tiles to see if there is evidence of leaks. Look at the elbows at the ends of the drops for erosion damage. Look for longitudinal cracks in long runs. Look for where piping is bowed (if it is plastic). Look for places where dissimilar metallic pipe materials have been joined (CI vs galvanized vs copper).

All this can be a long and daunting task. The first place I would look is the maintenance office. These guys, especially the ones who have been around a long time, have first hand knowledge of where failures and problems have occured and can give good info on where future problems might occur.

Try these as a start.